Oxford Nanopore Technologies Limited

Stuart William Reid

James Anthony Clarke

Gavin Harper

Clive Gavin Brown

Daniel John Turner

Andrew John Heron

James White

Steven Paul White

Gurdial Singh Sanghera

Terence Alan Reid

Christopher James Wright

Daniel George Fordham

Roger Charles Gill

David Jackson Stoddart

A target polynucleotide is expanded. In respect of each nucleotide in the target polynucleotide, the target polynucleotide comprises clock nucleotides and at least one signal nucleotide in a predetermined order. The clock nucleotides have a predetermined sequence common to each nucleotide in the target polynucleotide. The at least one signal nucleotide is characteristic of the identity of the respective nucleotide in the target polynucleotide. During translocation of the expanded polynucleotide through a nanopore, electrical measurements dependent on the polynucleotide within the pore are made, to derive an analysis signal. Clock signals derived from the clock nucleotides are identified. Relative to the positions of the identified clock signals, nucleotide signals derived from the least one signal nucleotide are derived to analyse the target polynucleotide. The predetermined sequence of the clock nucleotides comprises a restriction site for a restriction enzyme and at least one further nucleotide that extends the predetermined sequence.

Analysis of a polynucleotide via a nanopore system

A sequence of polymer units in a polymer (), eg. DNA, is estimated from at least one series of measurements related to the polymer, eg. ion current as a function of translocation through a nanopore (), wherein the value of each measurement is dependent on a k-mer being a group of k polymer units (). A probabilistic model, especially a hidden Markov model (HMM), is provided, comprising, for a set of possible k-mers: transition weightings representing the chances of transitions from origin k-mers to destination k-mers; and emission weightings in respect of each k-mer that represent the chances of observing given values of measurements for that k-mer. The series of measurements is analysed using an analytical technique, eg. Viterbi decoding, that refers to the model and estimates at least one estimated sequence of polymer units in the polymer based on the likelihood predicted by the model of the series of measurements being produced by sequences of polymer units. In a further embodiment, different voltages are applied across the nanopore during translocation in order to improve the resolution of polymer units.

Method and system of estimating a sequence of polymer units

To form a layer separating two volumes of aqueous solution, there is used an apparatus comprising elements defining a chamber, the elements including a body of non-conductive material having formed therein at least one recess opening into the chamber, the recess containing an electrode. A pre-treatment coating of a hydrophobic fluid is applied to the body across the recess. Aqueous solution, having amphiphilic molecules added thereto, is flowed across the body to cover the recess so that aqueous solution is introduced into the recess from the chamber and a layer of the amphiphilic molecules forms across the recess separating a volume of aqueous solution introduced into the recess from the remaining volume of aqueous solution.

Formation of layers of amphiphilic molecules

A time-ordered series of measurements of a polymer made during translocation of the polymer through a Nanopore are analysed. The measurements are dependent on the identity of k-mers in the Nanopore, a k-mer bring k polymer units of the polymer, where k is a positive integer. The method involves deriving, from the series of measurements, a feature vector of time-ordered features representing characteristics of the measurements; and determining similarity between the derived feature vector and at least one other feature vector.

Analysis of measurements of a polymer

Method of operating a measurement system to analyze a polymer

Nanopore arrays for sequencing nucleic acids

The invention relates to a new method of determining in a sample the presence or absence of one or more analyte members of a group of two or more analytes. The invention therefore relates to a multiplex assay for determining the presence or absence of each analyte in a group of multiple analytes. The assay uses aptamers and transmembrane pores.

Aptamer method

A biochemical analysis system analyses polymers by taking measurements of a polymer from a sensor element comprising a nanopore during translocation of the polymer through the nanopore. When a polymer has partially translocated, the series of measurements is analysed using reference data derived from a reference sequence to provide a measure of similarity. Responsive to the measure of similarity, the sensor element may be selectively operated to eject the polymer and thereby make the nanopore available to receive a further polymer. Where the biochemical analysis system comprises an array of sensor elements and is takes measurements from sensor elements selected in a multiplexed manner, responsive to the measure of similarity, the biochemical analysis system ceases taking measurements from the currently selected sensor element and to starts taking measurements from a newly selected sensor element.

Analysis of a polymer

Analysis Of A Polymer A biochemical analysis system analyses polymers by taking measurements of a polymer from a sensor element comprising a nanopore during translocation of the polymer through the nanopore. When a polymer has partially translocated, the series of measurements is analysed using reference data derived from a reference sequence to provide a measure of similarity. Responsive to the measure of similarity, the sensor element may be selectively operated to eject the polymer and thereby make the nanopore available to receive a further polymer. Where the biochemical analysis system comprises an array of sensor elements and is takes measurements from sensor elements selected in a multiplexed manner, responsive to the measure of similarity, the biochemical analysis system ceases taking measurements from the currently selected sensor element and to starts taking measurements from a newly selected sensor element.

A target polynucleotide is expanded. In respect of each nucleotide in the target polynucleotide, the target polynucleotide comprises clock nucleotides and at least one signal nucleotide in a predetermined order. The clock nucleotides have a predetermined sequence common to each nucleotide in the target polynucleotide. The at least one signal nucleotide is characteristic of the identity of the respective nucleotide in the target polynucleotide. During translocation of the expanded polynucleotide through a nanopore, electrical measurements dependent on the polynucleotide within the pore are made, to derive an analysis signal. Clock signals derived from the clock nucleotides are identified. Relative to the positions of the identified clock signals, nucleotide signals derived from the least one signal nucleotide are derived to analyze the target polynucleotide. The predetermined sequence of the clock nucleotides comprises a restriction site for a restriction enzyme and at least one further nucleotide that extends the predetermined sequence.

The invention relates to a method for modifying a template polynucleotide for characterization, especially for nanopore sequencing. The method produces a modified polynucleotide which is complementary to the template polynucleotide at some positions and which contains universal or abasic nucleotides at the other, and in some instances predicable, positions. The resulting modified polynucleotide can then be characterized.

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Oxford, United Kingdom

Stuart William Reid